Automatic positioning means



June 9, 1942. H. HARVEY ETAL AUTOMATIC POSITIONING MEANS Filed July 26,1941 WZMM QM NM Patented June 9, 1942 AUTOMATIC POSITIONING MEAN 8Herbertllarvey and Ralph s. Thacker, Los An- .geles, Calm, assignors toLeo M. Harvey, La.

Canada, Calif.

Application July 20, 1941, Serial No. 404,180

@laims.

This invention relates to controls and relates more particularly to acontrol or means for operating and controlling moving machine elements.A general object of this invention is to provide a system or means ofthis character which automatically brings the moving element to a givenor selected position each time operation of the element is terminated.

In machines and devices of various kinds it is often desirable to causea moving part to come to rest in a given or known position each time itis to be stopped. For example, in commercial washing machines it ishighly desirable to bring the rotating cylinder to a given position atthe completion of the washing operations. In commercial washing machinesthe clothes are placed in a perforated rotatable tumbler or cylinderwhich in turn operates in a shell containing the water, washingmixtures, etc. The surrounding shell and cylinder have openings throughwhich the articles being washed are passed and these openings havesuitable doors. To facilitate the loading and unloading of the cylinderit is necessary to bring the cylinder to a position where its openingcommunicates with the opening of the shell and it is highly desirable tobring the open logs into perfect or substantially perfect registrationto facilitate the safe operation of the doors and to prevent the clothesor materials from being caught between the cylinder and shell. In thewashing machines now in general use the cylinder may stop in anyposition at the conclusion of the Washing operations and the operator isobliged to employ'inching switches to inch or shift the cylinder to thecorrect position by successive stages. This inching operation istedious, time consuming and unsatisfactory for obvious reasons.

An important object of this invention is to provide dependable,eilicient and entirely automatic means for accurately positioning amoving or rotating element in a selected or known position each timemovement or operation of the element is terminated.

A more specific object of this invention is to provide means forautomatically positioning the rotatable cylinder of a commercial washingmachine where its access door is in registration with the door of theshell each time operation of the cylinder is'terminated. The automaticpositioning means of the invention operates to bring the cylinder doorinto registration with the door of the shell regardless of what positionthe cylinder happens to be in when the operator or a control mechanismacts to discontinue cylinder operation.

Another object of this invention is to provide a positioning means ofthe character referred to that is accurate and rapid in operation,bringing the cylinder or moving part to the required position with aminimum range of possible inaccuracy and in the shortest time possible.The cylinder or moving part is always stopped with its access openingand door within a very few inches, say, from 1 to 3 inches oi. exactregistration with the shell door without hunting" or time consuming backand forward movements of tion.

Another object of this invention to provide a positioning means of thecharacter "eferred to that always produces final movement of thecylinder in a given direction, which I will term the up direction, tobring the cylinder tothe door registering position so that the clothesor materials in thecylinder are in the most advantageous position .forremoval when the cylinder is stopped.

A further object of this invention is to provide a positioning means ofthe character referred to that may be used with a manually operatedcontrol such as a manually operated switch for terminating cylinderoperation or may he used with an automatic control such as the automaticcycle governing mechanism employed in commercial washing machines fortiming the operation of the cylinder and other elements or the machines.

The variousfobjects and features of the invention will be fullyunderstood from the following detailed description of a typicalpreferred form and application of the invention, throughout whichdescription reference is made to the accompanying drawing, in which:

The drawing is a wiring diagram of thecircults embodied in the inventionwith certain parts of a washing machine and certain elements of thecontrol mechanism illustrated in a diagrammatic manner.

or restricted to the specific form or application about to be describedbut is to be taken as including any features or modifications that mayfall within the scope of the claims.

The portion of the washing machine illustrated includes a stationaryshell l8 adapted to contain the washing mixtures, water, bleachcs, etc,employed during the successive operations. A suitable opening H isprovided in the wall of the shell N in a position where it is accessibleto the operators and the opening is closed by a door l2 when the machineis in operation. A hollow perforated cylinder I3 is rotatable within theshell l8. The cylinder I3 is provided to receive and contain the clothesor articles to be washed and has the usual lifting ribs I 4 to lift andtumble the clothes. An opening I5 is provided in the wall of thecylinder l3 through which the clothes or materials are inserted andremoved and the opening I5 is closed by a suitable door |8 when themachine is in operation. The cylinder I3 is supported in concentricrelation to the shell l8 for rotation therein and is driven by a shaft Hwhich in turn is operated or driven by a reversible motor M.

The mechanism or system of the present invention may be said tocomprise, generally. a normally operative control 28 for the cylindermotor M, switch means A. B and C operated by the cylinder l3, a relay 2|under the control of the switch means A. B and C and a stop switch 22adapted to be operated either manually or by an automatic timer andoperable to out out" the normally operative control 28 and to cut in therelay 2| so that the switch means A, B and C is rendered operative toposition and stop the cylinder l3.

The normally operative control 28 may be such as to cause continuous oruninterrupted rotation of the cylinder I3 in one direction during theperiod of cylinder operation or may be operable to cause alternativeright and left hand rotation of the cylinder during this period. In thecase illustrated, the control 28 is of the latter type, serving to causerotation of the cylinder l3 to the right, then to the left, then to theright, and so on, throughout the duration of cylinder operation. Themotor M is reversible and is supplied with operating current by a threewire power circuit |--2--3. The reversible motor M is operable to rotatethe cylinder in the right hand and left hand directions which I willherein refer to as the up" and down directions, respectively, and whichare so desi nated in the drawing. The normally operative control 28includes up and down relays 23 and 24 connected in the power circuit|2-3 to produce forward and reverse operation of the motor. The up relay23 includes three pairs of contacts 23', 23" and 23 connected with thethree power wires I, 2 and 3, respectively and the down relay 24 hascorresponding pairs of contacts 24, 24" and 24 which 'are connected inthe divided power circuit in the order 3-2-|, that is, the contacts 24*are connected with the wire I, the contacts 24 are connected with theacter.

wire 2 and the contacts 24 are connected with the wire 3. Common leads25, 28 and 21 extend from the "\ip and down relays 23 and 24 to themotor M. The lead 25 is connected with the stationary contacts 23 and24, the lead 28 is connected with the stationary contacts 23" and 24while the lead 21 is connected with the stationary contact 23 and 24.The relays 23 and 24 further include operating coils 28 and 28,respectively, for opening and closing their respective pairs ofcontacts. With the contacts of the "up" relay closed the cylinder I3 isrotated in the up direction as indicated in the drawing and when thecontacts of the down relay 24 are closed the cylinder I3 is rotated ithe down direction.

The normally operative control 28 further includes an automaticallyreversing timer for controlling the coils 28 and 29 of the up" and downrelays 23 and 24. may be of any well known type. In the present case itmay be considered as comprising a double throw switch 38 whose blade ormovable element 3| is connected in one side or lead 32 of a power line.The other side or lead 33 of the power circuit extends directly to onepole of each of the coils 28 and 29. A line 34 extends from the secondterminal of the coil 29. to one contact 35 of reversing switch 38 and asimilar line 38 extends i'rom the second terminal of the coil 28 to theother stationary contact 31 of the reversing switch. As diagrammaticallyillustrated, the blade 3| is spring biased or operated toward thecontact 35 by a spring 38 and is operated in the other direction toengage the stationary contact 31 by a winding or coil 39. The coil 39 isconnected. in the power line 32 and the power line 32 is controlled by asuitable make and break mechanism 48 so that the coil 39 is energizedduring given periods and is deenergized during the intervals betweenthese periods. The make and break mechanism 48 may be driven by themotor M and may be of any selected char- For this reason the details ofthe mechanism 48 have been omitted from the present disclosure.

The switch means A--BC governs the motor M through the medium of therelay 2| to position and stop the cylinder |3 where its opening I5 is inregistration with the shell opening II. The switch means AB-C comprisesa cam or part 42 movable with the cylinder l3 and the three spacedswitches A-BC are controlled or operated by the cam. The cam 42 may bemounted in any selected manner to rotate with the cylinder l3. In thecase diagrammatically illustrated the cam 42 is at the periphery of thecylinder I3, it being understood that this is merely illustrative andthat in most instances it is preferred to arrange the cam 42 at theexterior of the shell, for example. on a sprocket, wheel or other partsecured to the cylinder I3 or shaft II. The cam 42 is of substantialcircumferential length, its length being dependent upon the spacing ofthe switches A and B and upon other factors as will later becomeapparent. The opposite ends of the cam 42 incline or slope up to thecrest of the cam which is concentric with the axi of rotation of thecylinder l3. The switches A, B and C may be of any selected typesuitable for operation by the cam 42. It is preferred to employ switchesA, B and C that operate with slight movement and that are positive.

The switch A may be termed the condition switch" as it conditions therelay 2| for the cyl- This reversing timer t assure inder positioningand stopping operation. The switch Acomprises an inner pair of contacts43 and 44, an outer pair of contacts 45 and 45 and a contactor 41movable between an in position where it electrically connects thecontacts 43 and 44 and an out position where it electrically con- :nectsthe contacts 45 and 46. The contactor 41 is normally in the in positionin cooperation with the contacts 43 and 44, as illustrated, being springurged or gravity urged to this position. The contactor '4! is arrangedto be moved outwardly by the cam 42 to the out position where it isclear of the contacts 43 and 44 and where it electrically connects thecontacts 45 and 48..

The switch B is the stopping switch, serving to de'energize the motor Mand cause operation of a brake 48 associated with the motor M. inaccordance with the invention the switch B is spaced forwardly from theswitch A relative to the up direction of rotation of the cylinder it. Thswitch B includes a pair of contacts 49 and 50 and a contactor adaptedto electrically connect the contacts 49 and 50. The contactor 5| isarranged to be operated outwardly by the cam 42 to a position clear ofthe contacts. 49 and 5| The contactor Si is normally in cooperation withthe contacts 49 and 59, being spring or gravity urged to its inposition. tactors 41 and 5| of the switches A and B is greater than theeifective length of the cam 42 so that the cam cannot bridge the twocontactors to cause simultaneous operation of the switches A and B butthe distance between the contactors 4i and 5| need not be more than afew inches greater than the length of the cam.

The switch C may be termed a "safety switch as it serves to assurecorrect operation of the system in the event the stop switch 22 isoperated in the same time the cam 42 is holding the contactor 411 of theswitch A in its out position during down rotation of the cylinder l3which occurrence would otherwise result in continuing rotation of thecylinder. The switch C may be similar to the switch B, comprising a pairof contacts 52 and 53 and a shiftable contactor 54 engageable with thecontacts to electrically conmeet the same. The contactor 54 may be sping or gravity actuated to the in position where it cooperates with thecontacts 52 and 55 and where it is adapted to be moved out of engagementwith the contacts by the cam 42. The switch C may be located at anyselected point in the path of the cam 42 except in that zone lyingbetween the switches A and B or the zone immediately on the down side oithe switch A. maybe preferred to space the switch C some distance fromthe switch A as illustrated.

The brake. 48 is provided to stop the cylinder i3 when movement of thecylinder has been greatly retarded by the action of the positioningsystem and serves to hold the cylinder in the position where the openingI5 is in register with the opening H. The brake 48 may be associatedwith the motor M and may comprise a plate or disc 55 fixed to the shaftI1 and a similar disc 56 slldable on the shaft l1 and equipped withfriction material for contacting the disc 55. A lever 51 has one endoperatively connected with the disc 56 and its other end pivotallyconnected with the armature or shiftable element 58 of a solenoid coil59. A spring 60 is arranged undcr compression between the shiftable disc55 and a stationary abutment and tends to force the disc 56 against thedisc 55 to produce the braking effect. The solenoid 59 of the brake 48The space between the con-" In practice it may be connected in theoperating circuit of the motor M to remain energized so long as themotor M is energized. In the drawing one lead 5| of the solenoid 59 isconnected in the motor lead and the other lead 62 of the solenoid 59is.connected in the motor lead 21. With the solenoid 59 energized duringenergization of the motor M the solenoid 59 holds the lever 51 in theposition where the disc 56 is clear of the disc 55. as shown in thedrawing. When the motor M and the solenoid 59 are deenergized the spring60 forces the disc 56 into engagement with the disc 55 to stop movementof the cylinder l3 and to' hold the cylinder against further movement.

%e relay 2| is put into operation when the cam 42 moves the contactor 4iof the switch A into engagement with the contacts 45 and 45.

assuming the stop switch 22 has been operated,

and the relay thereupon serves to govern the motor M in such a mannerthat the cylinder I3 is stopped when the cam 42 comes into cooperationwith the switch B. The relay 2| includes a solenoid 63, three movablecontacts 64, 65 and 66 controlled by the solenoid 63 and three stationary contacts 61, 68 and 69 engageable by the movable contacts 64, 65 and56, respectively.

The movable contact 64 is connected to the power line 32 by a lead I0and a line H extends from the mated stationary contact 61 to the contactof switch A and has an extension I2 continuing from the contact 46 ofswitch A to the lead Hi or the power line 32. A line 13 extends from oneterminal of the solenoid 83 through the switch (3 to lead ll and a leadI4 extends from the other terminal of solenoid 63 to the power line 33.It will be seen that upon operation of the contaotor 41 by the cam 42that a circuit will be temporarily completed through the line 75, theswitch C. the line ll, the contacts 45 and 46 and the line l2 to thepower line 32 and through the lead 15 from the other power line 33 tothe other terminal of the solenoid 53. Thus, the relay 2| is energizedupon outward movement of the contactor 47 of switch A. Energization ofthe solenoid 53 brings the contact 64 against contact B1 and asustaining circuit for the solenoid 53 is completed through the lead Hi,the contacts.

64 and 61, the lead 1| the switch C and the lead 13. From the above itwill be seen that engagement of the cam 42 with the contactor 41 of theswitch A will put the relay 2i into operation assuming the stop switch22 has been operated, as will be later described.

The relay 2| is operable to cause energization of the down relay 24 ofthe motor circuit so that the motor M may act as a retarding means orbrake to lessen the rate of movement of the cylinder IS in the event thecylinder i3 is turning in the up direction. As above described, the lead34 extends from one terminal of the coil 29 of down relay 42 to thereversing switch 35 for connection thereby with the power line 32. Theother power line 33 may be directly connected with the other terminal ofthe coil 29. When the stop switch 22 is operated. as will be later deingmovable contact 55 of relay 2| to the contact of switch B. A branched orcommon lead 11 connects the contacts 49 of switch B and 44 of switch Awith the above described lead 12. When the relay 2| is energized acircuit is completed through the coil 28 of the "down relay 24 throughthe leads 34 and 16, the contacts 68 and 65, the lead I6, the closedswitch B,'and the leads II and 12. In this connection it will beobserved that the switch B is interposed in the energizing circuit ofthe coil 28, that is, the circuit of the coil 29 which comes into usefollowing operation of the stop switch 22 and the switch A.

The relay 2|, prior to its energization and subsequent to operationofthe stop switch 22, completes a circuit to the coil 28 of the up"relay 23 and when the relay 2| is energized or operated the circuit tothe up" relay 23 is broken. One terminal of the "up" relay coil 28 isdirectly connected in the power line 33 and, as above described, a line36 extends from the other terminal of the coil 28 to the reversingswitch 38. A lead I8 extends from the lead 36 to the stationary contact63 of relay 2|. A lead I9 extends from the movable contact 66 of relay2| to the contact 43 of switch A. The above mentioned lead 11 isconnected with the other inner contact 44 of switch A so that contact 44is in electrical connection with the power line 32. Accordingly, in theevent the stop switch 22 is operated when the cylinder I3 is moving inthe "up" direction, the circuit to the up relay 23 is maintained and thecylinder will continue to rotate in this direction. As will later becomeapparent, operation of the stop switch .22 to terminate operation of thecylinder I3 results in disconnection of the down relay 24 from itsenergizing circuit and closes the circuit to the solenoid 28 of the "uprelay 23 through the line I8, the contacts 66 and 69, the lead I9, theswitch A and the leads 'I'I The stop switch 22 may either be a manuallyoperated switch or a switch automatically con trolled by a timer orother automatic means. When the stop switch 22 is operatedfrom thenormal position where the cylinder I3 isin operation to the positionillustrated in the drawing the switch transfers the control of the motorM from the relays 23 and 24 to the relay 2|. The stop switch 22 isinterposed in the power line 32, having movable contact 88 and astationary contact 8| connected in the line 32 ahead of the reversingswitch 38. When the movable contact 88 is in engagement with the contact8| the circuit is completed through the lead 32 and the reversing switch38 to the relay 23 or 24, as the case may be, and the make and breakmechanism 48. The stop switch 22 includes a second stationary contact 83forming the terminal of the above described leads I8 and I2. When themovable contact 88 is brought into cooperation with the contact 83, thecircuit to the coil 23 of the down relay 24 is broken because thereversing switch 38 is no longer effective and the circuit to the coil28 of the up" relay 23 is completed to continue to rotate in the up"direction in the event it is already turning in that direction or ismade to turn in the up direction in the event that it has been turningin the "down direction.

In the operation 01 the system it will be first assumed that the stopswitch 22 is operated from its normal position to the positionillustrated in the drawing at a time when the cylinder I3 is rotating inthe up direction. In this event, the reversing switch 38 is cut out sothat the make and break mechanism 48 is no longer operative in causingalternate up and down rotation of the cylinder I3. Operation of the stopswitch 22 closes a circuit to the coil 28 of the "up" relay 23 throughthe line I2, the lead 11, the switch A, the lead I3, thenormally closedcontacts 66-63 of relay 2| and the leads I8 and 36. Accordingly, uprotation of the cylinder I3 continues and is assured until the cylinderis brought to a stop. Rotation of the cylinder I3 brings the cam 42 intocooperation with the contactor 41 of switch A. Operation oi thecontactor 41 by the cam 42 breaks the above described circuit throughthe normally closed contacts 66 and 68 01' relay 2| to the up relay coil23 and temporarily completes a circuit to the coil 63 of relay 2|. Thistemporarily completed circuit comprises the lead I4 to one terminal ofthe coil 63, the lead I3 extending through switch C, the lead Iiextending to contact 46 of switch A and the lead 12 extending fromcontact 46 of switch A to the stop switch 22 which connects it with theother side 32 of the power line. Temporary or momentary operation ofrelay 2| resulting from momentary operation of switch A by the cam 42,as just described, completes a sustaining circuit to the coil 63 ofrelay 2|. The sustaining circuit of the coil 63 includes the lead I4extending from one power line 33 to the coil 63. the lead I3 extendingfrom the coil 63 through the switch C to lead I I, the engaged contacts64 and 61, and lead I8, which is connected with the other power line 32by the operated stop switch 22. Thus, it will be seen that operation ofthe switch A by the cam 42 first produces momentary energization ofrelay 2| and this in turn results in sustaining of the relay-2| throughthe circuit just described.

With the coil 83 of relay 2| operated the circuit to the up relay coil28 is broken and a circuit is completed to the coil 29 of the down relay24 through the switch B. With the coil 63 energized the contact 68 isout of engagement with the contact 69 so that the circuit to the coil 28of the up relay 23 is broken. So long as the coil 63 of relay 2| isenergized a circuit is completed through the coil 23 oi. down relay 24through the leads 34 and I5, the made contacts 68 and 65, the leads 16,the switch 18, the lead II, the lead 12 and the stop switch 22 whichconnects lead I2 with power line 32. When the up" relay 23 isdeenergized and the down relay 24 is energized, as just described, themotor M is energized and serves to retard, brake or slow down the up"rotation of the cylinder 3. The cylinder I3 is usually quite heavy andusually contains a mass of wet clothes, or the like, and thus hassubstantial inertia. The braking or retarding action of the reversedmotor M slows the rotation of the cylinder I3 but the inertia of thecylinder carries the cylinder on so that the cam 42 moves from theswitch A to the switch B. However, by the time the cam 42 reaches theswitch B the cylinder I3 is turning at a very slow rate.

When the cam 42 operates the contactor 6| outwardly from the stationarycontacts 43 and 58 the circuit to the coil 29 of the down" relay 24 isbroken, this circuit having been followed in detail above. Opening ofswitch B by the cam 42 results in complete deenergization of the motor Mand the brake coil 59, the up" relay coil 28 having been deenergizedupon energization of the relay 2|, as above described. Upondeenergization of the coil 59 the spring 68 operates the brake disc 56against the disc 55 and the cylinder I3 is stopped. The cylinder I3 isturning at a very slow rate and with little inertia when the brake meansgoes into operation and the brake means 48 is effective in stopping thecylinder II in the position where the cam 42 holds the switch B open.Further, and of particular importance, is the fact that the brake means48 stops the cylinder i3 in a position where its opening ill is inregistration with the opening I i. The spacing of the switch B from theswitch A and the proportioning oi the cam 42 assures the stopping of thecylinder 13 in the position where its opening i is in register with theopening H of the shell iii.

t is to be understood that the stop switch 22 is retained in theposition illustrated in the drawing for a given period, eithermechanically or manually, during the above described cylinder stoppingoperations. In actual operation this period in which the switch 22 isheld in the position illustrated is relatively short as the cylinderstopping and positioning operations above described require only a shorttime for their completion, but these operations vary slightly dependingupon the position of the cam 42 at the time f reversal or operation ofthe stop switch 22.

it will now be assumed that the washing machine is in operation and thatthe switch 22 is operated from its normal position to the positionillustrated at a time when the cylinder I 3 is turning in the down"direction. As above described, operation of the stop switch 22 to theposition illustrated in the drawing disconnects or cuts out the coil 29of the down relay 24 because the lead 34 from the coil 29 is connectedwith the power line 32 through the reversing switch 30 and the operatedstop switch 22 cuts out the reversing switch 30. Operation of the stopswitch 22 to the position illustrated also serves to complete a circuitto the coil 28 of the up" relay 23 through the leads 36 and 18, thenormally closed contacts 68-69 of relay 2|, the lead 19, the switch A,the leads H and 72 and the stop switch 22, the stop switch 22 beingcoupled with one side 32 oi the power line and the other side 33 oi thepower line being coupled with the coil 2B. Dperatiori of relay 23reverses the motor M and causes the cylinder 13 to reverse its directionof rotation, that is, to turn in the up" direction instead of the downdirection. The cam 42 may be at any rotative position when the reversalof direction of rotation of the cylinder l3 occurs.

In any event, the cam 42 ultimately comes into operative engagement withthe contactor 41 of switch ii. it will be apparent that when the cam 42moves into operative engagement with the contactor 4i oi the switch Aduring rotation of the cylinder 63 in the up" direction the systemoperates as described above in the example where it was assumed that thecylinder 13 was turning in the up direction when the switch 22 wasoperated. In other words, operation of the switch A by the cam 42initiates the above described sequence of operationscausing the "uprelay 24 to be energized so that the cylinder 13 is slowed down by thereversed motor M to be stopped by the brake means 48 when the cam 42operates switch B to deenergize the motor M.

It will be observed that in the above described operations the switch Cdid not perform any function. The operation of the switch C by the cam42 during the above described operations having no eflect on the controlsystem, the switch C merely being temporarily opened without producingany result. The switch C is incorporated is interposed in the line 13extending from one event the stop switch 22 is operated, to the positionillustrated, at a time when the cylinder I3 is turning in the down"direction and at the particular time when the cam 42 is holding thecontactor 41 of switch A in cooperation with the contacts and 46.Assuming that the switch 22 is operated to the position shown at thisparticular time the circuit to the coil 63 of the relay 2| is completedthrough'the lead 13, the switch C, the lead H, the outer contacts 45 and45 of switch A, the lead 12 and the stop switch 22, the other side ofthe coil -63 being connected in the power line 33 by lead 14. As abovedescribed, energization of the coil 63 breaks the circuit through thenormally closed contacts 66 and 69 to the up relay 23 and completes acircuit to the coil 29 of the down relay 24 through the contacts and 68and the leads connected therewith. Accordingly, the "down rotation ofthe cylinder 13 continues after the cam 42 has left switch A.

The cylinder l2 continues to turn in the down direction and the cam 42ultimately opens switch C. Opening of switch C breaks the circuit to thecoil 63 of relay 2| as switch C terminal of the coil. Relay 2i restoresto its normal condition where the contacts 66 and 69 are closed tocomplete the circuit to the coil 28 of the up relay 23 and where thecoil 29 of the down relay is deenergized. With the up relay 23 energizedand the "down relay 24 deenergized the motor M is reversed to cause thecylinder I3 to rotate in the up direction. The

cam 42 on the cylinder I3 moves up toward the switch A and ultimatelyoperates switch A. This operation of switch A initiates the abovedescribed series of operations and the system acts exactly the same asin the example described where the stop switch 22 isoperated when thecylinder i3 is rotating in the up direction. The switch C is positionedsome distance from the switch A so that the cylinder l3 will have gainedsuitable. momentum or inertia by the time the cam reaches switch A, thusassuring subsequent movement 0i the cam 42 into cooperation with switchB to stop the cylinder l3, all as described above.

Having described only a typical preferred form and application of ourinvention, we do not wish to be limited or restricted to the specificdetails herein set forth, but wish to reserve to ourself any variationsor modifications that may appear to those skilled in the art or fallwithin the scope of the following claims.

Having described our invention, we claim:

1. In combination, a moving element, power means for moving the element,mean for reversing the 'power means, the reversed power means serving toreduce the inertia of the rotating element, means for rendering thepower means ineffective in either direction a given time followingoperation of the reversing means and for holding the elements againstmovement when p the inertia of the element has reached a very low valueand before the element has begun reverse movement, and switch means forinitiating operation of the reversing means.

2. In combination, a rotatable element, reversible power means forrotating the element, means for reversing the power means operable whenthe element reaches a given position, the reversed power means servingto reduce the inertia ,of the rotating element, and means operin thesystem to assure correct operation in the,

ble power means for rotating the element, means for reversing the powermeans operable when the element reaches a given position, the reversedpower means serving to reduce the inertia of the rection, elementpositioning means operable following operation of the control means todeenerrotating element, a circuit governing the reversing means having aswitch operable to condition the reversing means for operation, andmeans operable following operation of the reversing means for renderingthe power means ineffective when the reversed power means has slowed theelement to a substantial stop at a given position and before the elementbegins reverse movement.

4. In combination, a rotatable element, reversible power means forrotating the element, means for reversing the power means, means for putting the reversing means into operation comprising a circuit controllingthe reversing means, a switch in the circuit and a part rotatable withthe element for operating the switch, and means for discontinuingoperation of the power means when the reversed power means has broughtthe element substantially to a stop and before the element beginsreverse movement.

5. In combination, a rotatable element, reversible power means forrotating the element, means forvreversing the power means, means forputting ,the reversing means into operation comprising a circuitcontrolling the reversing means, a switch in the circuit and a partrotatable with the element for operating the switch, and means fordiscontinuing operation of the power means when the reversed power meanshas brought the element substantially to a stop and before the elementbegins reverse movement comprising a switch operable to deenergize thepower means and operable by said part.

6. In combination, an enclosing structure having an opening, an elementrotatable in the structure and having an opening adapted to registerwith the opening thereof, reversible power means for rotating theelement, reversing means for causing alternate operation of the elementin opposite directions, a relay operable to cause operation of the powermeans in one direction and then in the other direction, switch meansoperable to transfer control of the power means from the reversing meansto the relay, switch means made operative upon actuation of the firstnamed switch means and operable by movement of the element ineitherdirection to put the relay into operation at a given phase of rotationof the element so that rotation of the element in said other directionslows the element. and switch means made operative with the relay fordeenergizing the power means and relay to stop the element where saidopenings are in communication.

'7. In combination with a rotating element and a reversible drive forthe element having a normally operative reversing means for causingalternate rotation of the element in opposite directions, control meansoperable to cause operation of the power means in one direction when thegize the power means and control means when the element has continued toturn in said opposite direction to a given position, and means operableto transfer control of the power means from said reversing means to saidcontrol and energizing the power means to rotate the element in said onedirection until said control comes into operation. a

8. In combination with a rotating element and a reversible drive for theelement having a normally operative reversing means for causingalternate rotation of the element in opposite directions, control meansoperable to cause operation of the power means in one direction when theelement is in a given rotative position regardless of the direction theelement may be rotating, said operation of the power means in said onedirection tending to slow down the element in the event the element isturning in the opposite direction, element positioning means operablefollowing operation of the control means to deenergize the power meansand control means when the element has continued to turn in saidopposite direction to a given position, brake means operated uponactuation of the position- I ing means for stopping the element, andmeans operable to transfer control of the power means from saidreversing means to said control and energizing the power means to rotatethe element in said one direction until said control comes intooperation.

9. In combination with a rotating element and a reversible drive for theelement having a normally operative reversing means for causingalternate rotation of the element in opposite directions, control meansoperable to cause operation of the power means in one direction when theelement is in a given rotative position regardless of the direction theelement may be rotating, said operation of the power means in said onedirection tending to slow down the element in the event the element isturning in the opposite direction, element positioning means operablefollowing operation of the control means to deenergize the power meansand control means when the element has continued to turn in saidopposite direction to a given position, means operable to transfercontrol of the power means from said reversing means to said control andenergizing the power means to rotate the element in said one directionuntil said control comes into operation, and safety means for preventingcontinued rotation of the element in said one direction in the event thelast named means is operated when the element is in said given position.

10. In combination with a rotating element and a reversible drive forthe element having a normally operative reversing means for causingalternate rotation of the element in opposite element is in a givenrotative position regardless of the direction the element may berotating, said operation of the power means in said one directiontending to slow down the element in the event the element is turning inthe opposite didirections, control means operable to cause operation ofthe power means in one direction when the element is in a given rotativeposition regardless of the direction the element may be rotating, saidoperation of the power means in said one direction tending to siowidownthe element in the event the element is turning in the oppoenergizingthe power means to rotate the element in said one direction until saidcontrol comes into operation and a safety switch for preventingcontinued operation of the element in said direction in the event thelast named means is operated at the time the element is in saidposition.

11. In a washing machine, a shell having an opening, a cylinderrotatable in the shell and having an opening, power means for rotatingthe cylinder in both directions during operation of the machine, andmeans controlling the power means to cause the cylinder to turn throughits inertia in a direction so that its opening moves upwardly to theopening in the shell while the power means is tending to turn thecylinder in the opposite direction and to stop with its opening inregister with the opening in the shell regardless of the direction inwhich the cylinder may be turning when the last named means is put intooperation.

12. In a washing machine, a shell, a rotatable cylinder in the shell,the shell and cylinder having openings in their side portions, powermeans for rotating the cylinder, means for reversing the power means forcausing alternative rotation of the cylinder in opposite directions, andcylinder stopping and positioning means controlling the power means toturn the cylinder so that its opening moves up to the opening in theshell through its inertia and while the power means is tending to turnthe cylinder in the opposite direction to overcome the inertia and thenstop the cylinder with the openings in register irrespective of thedirection the, cylinder may be turning when the stopping and positioningmeans is put into operation.

HERBERT HARVEY. RALPH S. THACKER.

